Viscosity reduction of petroleum



Patented Nov. 30, 1948 VISCOSITY REDUCTION OF PETROLEUM MAHOGANY SULFONATE HYDROCAR- BON SOLUTIONS Leo Liberthson, New York, N. Y., and Jacob Faust, Belleville, N. J., assignors to L. Sonneborn Sons, Inc., a corporation of Delaware No Drawing. Application November 23, 194.6,

' Serial No. 711,838

7 Claims. 1

This invention relates to new and useful improvements in the viscosity reduction of petroleum mahogany sulfonate hydrocarbon solutions.

Petroleum mahogany sulionate solutions in organic solvents of the Water immiscible type are used for a variety or purposes such as wettin agents, emulsifying agents and the like. Ordinary petroleum mahogany sulfonates impart to their solutions a relatively high viscosity. In some cases this high viscosity is not critical regarding the purpose for which the sulfonate solutions are to be used. There are, however, many cases in which a relatively high viscosity is undesirable or detrimental to their intended use or application. This is, for example, true in textile processing such as of wool, worsted, rayon, viscose or the like, in which the various processing steps involved in the conversion of the raw material into fibres, the formation of the fibres into threads and the weaving of the threads into fabric, require the presence of a lubricating agent having a Saybolt viscosity of below 600 and preferably below 300 seconds Saybolt at 100 F. The latter is particularly true of textile lubricants used in the processing of synthetic fibres. In the case of textile processing it is for instance desirable to have a hydrocarbon textile lubricant composition with a sulfonate content of in excess of 28% mahogany sulfonates so as to render the composition not only readily and spontaneously emulsifiable but also to make the same readily wettable or rewettable on the fibre to thereby impart to the textile material substantial self-scourability. Hydrocarbon solutions of the textile lubricant type and containing in excess of 28% of .petroleum mahogany sulfonates possess, however, a viscosity far in excess of 600 seconds Saybolt at 100 F. and usually a viscosity in excess of 1000 seconds Saybolt at 100 F. For this reason it has been in the past necessary in such cases to limit the sulfonate content to a maximum of approximately in order not to exceed the usable viscosity for textile material treating purposes. Another example is the use of petroleum mahogany sulfonates in the compounding of cutting oil bases in which the relatively high viscosity and tackiness imparted to the composition by the sulfonate is an undesirable aspect interfering in many respects with the proper ease of application and use.

The relatively high viscosity of petroleum mahogany sulfonates in organic solvents is normally not subject to reduction by the addition of relatively low viscous diluents or thinning agents. This requires agents of such relatively low viscosity that they interfere with the lubricating properties of the composition. Furthermore, these solvents are then of the type which easily evaporate. This is particularly critical in the case of textile treating materials since the use of such thinning solvents will leave behind on the fibre upon evaporation a viscous sticky impregnant without adequate lubricating capacity on the fibre and will also interfere with the scourability of the impregnated material. On the other hand thinning with a solvent of the lubricant type diluent will not obtain the desired result as it is ncessary to add so much of the diluent as to bring the sulfonate content to below that necessary for adequate emulsification or other purpose for which the composition is designed.

One object in accordance with the invention comprises inter alia the viscosity reduction of a petroleum mahogany sulfonate solution in a substantially water immiscible organic solvent.

This and further objects of the invention will appear from the following description.

In accordance with the invention a suitable petroleum mahogany sulfonate solution in an organic substantially water immiscible solvent for said sulfonate is reacted with an oxidation agent in amount and for a period of time sufiicient to appreciably reduce the normally relatively high viscosity'of said solution due to the sulionate dissolved therein and preferably reduce said viscosity by at least one-third, said oxidation agent being one having an oxidation potential by virtue of the existence or liberation of O2.

Suitable oxidation agents may be either of the inorganic or organic type. Among inorganic oxidation agents useful in accordance with the invention satisfactory results may be obtained, for instance, with chromic acid, dichromates, permanganates, perchlorates, peroxides and similar materials. Among the organic oxidation agents. may be recommended particularly organic .peroxides and hyperperoxides, both aliphatic and aromatic, including for example butyl hyperperoxide, acetyl peroxide, benzoyl peroxide and like materials. The reaction conditions under which the oxidation agents in accordance with the invention produce an oxidation potential, including condtions of pH range, are well known in the art and need not be further exemplified here.

The solvents that may be used for preparation of the petroleum mahogany sulfonate solution to be treated should be substantiallyneutral to the action of the oxidation agent, are preferably such as will not appreciably dissolve inorganic salts,

and should be liquid at normal temperatures. added in aqueous solution. In the case of di- Suitable solvents that may be used in the practice chromates, the oxidation reaction is carried on on of the invention are, for instance, petroleum oil 'the acid side and in effect the oxidation potential distillates or any fraction thereof, benzol and its in such case is primarily that existing by reason homologs, naphtha,fl-.carbon tetrachloride; tetraof thec'formati'onof chromicacid. The treatchlorethanerchloroform; etc., and ingeneral any 'ment with 'theoxidationagent in accordance with aromatic or aliphatic or aryl or aralkyl h'ydrothe invention is continued until the desired viscarbon or hydrocarbon mixture, including their 'ncosity reduction is obtained, which may be as halogenated derivatives of a the ,aforedescribed .ceittained by the drawing of periodic samples and character and nature. in manyl.cases, par;ticu-"l0 the examination thereof on a suitable viscosilarl y' where the solvent is to be removed after the =meter. Maximum viscosity reduction may b viscosity reducing treatment, it is desirable to accompanied by color reduction, which in many have the boiling range of such solvent'sufii-ciently 1 casesmay beused-as an indication of the comlow to permit removal in the-*customary-manner, 'ple'tionof the viscosity reducing reaction. Color such as by distillation in vacuo or otherwise, "reduction to a Lovibond color value (10% white without causing thereby anywdecompositionof oil. solution 4/2" cell) of less than SR and preferthe mahogany sulfonates. In such cases Litiisof BIX Y-JCIOWn to 2-3R is usually d sirable. Whereadvantage that the boiling point be so low and ever the oxidation agent itself possesses a preferably between 75 and 250 F. astoenable tinctorial value, as is the case for instance with the removal of the sdlvent at ordinary tem- 0Q dichromates chromic acid, permanganates, etc.,

peratures without*the'necessity-of resorting to colon reduction cannot be used as a test. vacuumdistillation, :Where; ania'lkalin oracid pH may: be call d The-petroleum mahogany sulfonatewhichis for to aestablish --anoxidation potentialiiora subjected to the-viscosity reduction is normally particularioxidation agent in. accordance with the onederived from "-the*acid: refining with' fuming g5 rinventionpitiisiallways tolbe recommended thatian -sul=furic"acid of' a petroleumoil distillate-stock {EXCESS ofelkalinity or acidity-should be avoided. undersulfonating conditionsof -acid1amount and Such excess maycbedetrimental to -the efficiency temperature in accordance with a conventional re- 6f t i fredufitiom and furthermore "finingcpj'actige l g conventiomu fuming lgivexriselto.themartialdecomposition-of the sulu r e m e and id ludge 3O 'fon'atesaas .welliasn-in-many:casesto an undesirlayer are formedthe formerioontaining dissolved able color deterioration, rather, than color imth i zpetrolemn: aho ny t' lfoni acid 001-- iprovement.imltheresultant products. Since it is *lectively referred to as -=mahogany petroleum 'insmany leases IdGSiTabIGiitOHUtlHZB the ultimate 'snlfonic acids; l hese are recovered-from the oil 'xpl'oductsin substantiallyneutral form, it :may be '-1ayer in-accordance= with conventional methods :necessaryawhen theestablishing.or.existance of an "-in the form of solutions of-"these sulfonicacidsor -ldxidationpotential :calls for. an :acid pH, to neutheir salts (the latter being collectively termed etra'lize;the;zptoduct"resulting from thetreatment. petroleum*mtahoganysulfonates) in a portion 'lnlmaxny instances'suohneutralization,however,is of the oit'relatively tena'ciously occluded by these accompanied; by; lsomeainc-rease in iviscosi by: from "sulfonic bodies; Theconventional recovery of qothatlobtaininglzin:theneated product. This vispetroleum mahogany sulfonates in-eludes neuicosity:increasaormeversion is usually not sufiibraliza tionof the oil layer with caustic soda reidientlycritical:torintenferewith the ultimatelydesulting in the -forma'tion of the petroleum sired reduced viscosityxof-thexfinal-aproductuand ma hoganysodium sulfonates. The occluded oil cfonzthe pnrpose-foruvhich it is intended. By reai-s generally -referred to in the: art as "retained M5 .-s0n. ofthe viscosity reversion. upon neutralization, oil. I'l -he petroleum sulfonic. acids or sulfonate hcweveixit mayxbelinmany cases of dv n e "'oilncompo'sitions n'ormallly contain about to iparticularly'swhfin-low r range-viscosities are decrg5'%v .l g m d i:1:and1=s5. i1; :7.0% ofithe'petrosiredmosselect as the: oxidation agent onewith leum'-.'-mahogany :sulfonic material. L'Depending vihichzthegltreatment-may becarried out forthe -upon--theittype-,tand,Qltigifl ofxpetroleum oil disestablishingmfman ;oxidation;potential at .a neu- "iiil'la'tes from:whi'ch .th'ese -sulfonate oil solutions ii1fa1.=i:o;.alkaline pl-11sec as :torender unnecessary a .sor-z'stocksaare' derived, theycontain sulfonates of sneutralizationwhine-reaction.products. In this vvarying averagedzmolecularu weights. "For con- .caseiitismsually of advantage tozselect an agent venience therefore the sulfonatexstocksare idenzpermittingihejestablishing ofsan oxidation p0- stified by thei-r average molecular weights. .Thus, r :tentialrat apI-Irangeof; from 7;.to'8;5

-a:420:.or.'a50 sulfonate-"stock-is-as'stocl: inwhich Eependingmpon the oxidation .agent selected, the sulfonates :haveanzaverage molecular weight ;satisfacl;oryzresultsialte.lordinarily obtained with 10f 420M450 respectively. substantially lt-rom0.25i1toi3.% of 'oxidationagent :dnsathecpractical:application zoflth'e invention :by-weight..ofrsulfonatesspnesent in solution. .LthGTCIHdQ mahogany sulfonate in the organicnon .JIhe:ltemperaturecofreaction; is ordinarily not =;solvent' solution is intimately contacted with the critical. ,-Thei-reaction,;however,amay be facilitated oxidation-agent. rDepending-zuponther nature of :by increasing the temperature-to, for example, a fitlie oxidation agentgthe'. same may .beaadded in ip flf e te per e 0ffr0mto 0 F. This thezform of;aisuitableaqneousi or organic solvent ismarticularly desirable :with'more" heavily vis- -solution;: o1:;may be'iaddedzasisuch. :Someof the: T5101 8 s 1uti0na 1183 -t pe tu e Will riorganic :type 'Loxidation :agents are preferably increase;theffluidityrof the;solution; thus :permitadded as such'sincestheyiaregsoluble"in the type tingimoredntimate,contact between thereactants.

solvent 'usednfor th'e "s'ulfonate vsolution to be fl hezextent ltOWhjChilOW 'viscosity'values may be -;treated. Itisvhowever; also DOSSibIGBtO'KaddOXi- 2ohtain-edudepends,:- atzsleastrtoxsome extent, upon dation.agentsithateareenotsoasoluble.insuch p the type or or in f t p rol m m h any ---so1vent in the form ofrfinewdispersions and.main- :sul-fonate selected forithe-treatment, Ordinarily ,taining suitableagitations'so-asatoaassureconhigher average .:molecular .weight sulfonates tinned intimate contact i for nthe: .reaction. :In ,possess. a higherviscosity and :the resulting vis- ,-:most*casesthe; inorganic oxidation agents; :such :cositmafter treatment "is :usually commensurately as ,dichromates, lohromic lacid etc; 19.13.9 preferably :1 5 higherthan: :the viscosity zafter treatment 10f .ua

comparative er viscosity and in which the sulfonate had a lesser average molecular weight.

The ration of petroleum mahogany sulfonate to solvent is, as a rule, not critical except that it is desirable to so adjust the ratio that the viscosity of the solution is sufiiciently low at the desired or selected temperature of treatment to permit the intimate contact between the reactants. In most cases, however, a ratio of mahogany sulfcnate to solvent of substantially 2 to 1 (by weight) will give satisfactory results. Sulfonate concentrations above '70 to 75% sulfonate content are normally notdesirable for direct reaction without suitable extension. As a mode of agitation, any conventional method such as stirring, air-blowing, shaking, etc., may be used.

As above pointed out, the viscosity reducing reaction in accordance with the invention may be carried out with an organic solvent solution containing relatively high concentrations of petroleum mahogany sulfonate. In this case the resultant product is a concentrate which in many cases must be thereafter adjusted by the addition of organic solvent material of suitable viscosity, such as a suitable lubricant hydrocarbon, to the requisite petroleum mahogany sulfonate content desired for the specific purpose for which the composition is to be used. Thus, for instance, if it is desired to ultimately produce a textile treating oil having in excess of 28% petroleum mahogany sulfonate and a viscosity of less than 600 seconds Saybolt at 100 F., a concentrate having in excess of l0 and usually between 60 and 65% sulfonate, is first ob tained after the viscosity reducting reaction inaccordance with the invention, which product may be then extended by the addition of a suitable lubricant hydrocarbon, such as a mineral pale oil having a viscosity of 75 seconds Saybolt at 100 F. to a sulfonate content between 28 and 40% and a viscosity below 600 seconds Saybolt at 100 F.

Alternatively, the viscosity reducing reaction may be carried out with an organic solvent solution of a petroleum mahogany sulfonate already possessing the requisite final sulfonate content desired and intended for the purpose for which the viscosity reduced product is to be used. In

that case it is also of advantage to select for the solution such solvent as is desired for the final product, i. e., if a textile lubricating oil is intended to be ulitmately obtained, a textile lubricant having, for instance, a viscosity between 40 and 150 seconds Saybolt at 100 F. is selected as the solvent for the sulfonate. The product resulting from the viscosity reducing treatment is then per se usable after such further refining or purification as may be required for a textile treating oil.

Though in the operation of the novel viscosity reducing process any of the aforementioned solvents may be used with advantage, we prefer to use as the solvent that hydrocarbon fraction, the acid refining of which furnished the crude mahogany sulfonate stock and which is carried as retained oil. The crude mahogany sulfonateretainecl oil stock constitutes as such a convenient mahogany sulfonate solution that may be subjected directly to treatment in accordance with the invention.

Once a petroleum mahogany sulfonate has been subjected in suitable solvent medium to a vis- .cosity reducing reaction in accordance with the invention, it is possible to remove the solvent if desired and recover the petroleum mahogany sulfo'nates as such substantially free from solvent. These sulfonates when redissolved in the solvent still exhibit in solution the same reduced viscosity which they possessed prior to the removal of the solvent.

The following examples are furnished by way of illustration and not of limitation:

Example I lbs. of a petroleum mahogany sulfonate stock containingabout 61% sulfonate, about 37% retained oil and about 2% water, was used. The stock was obtained from a Mid-Continent distillate subjected in the conventional manner to white-oil refining with fuming sulfuric acid under sulfonating conditions. Mahogany sulfonates in the stock possessed an average molecular weight of 450, a Furol'viscosity of 132 seconds at 210 F. Upon dilution with a mineral pale oil ('75 seconds Saybolt at 100 F.) to a 30% sulfonate content, a viscosity of the solution of 1322 seconds Saybolt at 100- F. was obtained.

The original 61% sulfonate stock was acidifled with 66% H2SO4 to about 2% free sulfuric acid content and 1 lb. of potassium dichromate was added with agitation at a temperature of about to 200 F. Agitation and temperature were continued until a sample showed a viscosityreduction to 89 seconds Furol at 210 F. Upon dilution with a 75 vis. mineral pale oil to a 30% sulfonate content, a viscosity of the extended solution of 378 seconds Saybolt at 100 F. was obtained.

Example II 100 lbs. of the same 61% sulfonate stock used in Example I at a pH of about 7 to 8 was admixed with 1 1b. of potassium permanganate with agita' tion at a temperature of about 180 to 200 F. The treatment was continued until a sample showed a viscosity reduction of the mix to 51 seconds Furol at 210 F. Upon dilution with a mineral pale oil (75 seconds Saybolt at 100 F.) to a 30% sulfonate content, a reduced viscosity of 3'71 seconds Saybolt at 100 F. was obtained.

Example III Ewample IV l 100 lbs. of the same 61% petroleum mahogany sulfonate stock used in Example I was admixed at a pH of from 7 to 8 with 2 lbs. of acetyl peroxide with agitation at a temperature of about 180 to 200 F. The treatment was continued until a sample showed a reduced viscosity of about 72 seconds Furol. Upon dilution with a mineral pale oil (75 seconds Saybolt at 100 F.) to a 30% sulfonate content, a reduced viscosity of 506 seconds Saybolt at 100 F. was obtained.

Example V 100 lbs. of a 450 Mid-Continent petroleum mahogany sulfonate stock containing about 61% sulfonate, about 37% retained oil and about 2% water, obtained by a fuming sulfuric acid treatment as specified in ExampleI, having a Furol 7 .w'scosi-tynf il'2 i-sseconds'zatrz-loir .iwas used. -This --stock zwhen hilutedtiwithsazzminerali:pale oil ('75 seconds :Sayboltratolilt)"ii .)ntcs.a;i3ik% is'lilfonate content (showed; arvisoosity forctheidiluteda stock of 1892 seconds Saybolt atililflfiE.1:.l3heoriginal -.GI.%:'Sl.l1f0i13iteJStOGKlWaS r-admixedasatzazpH from 7 to 8 with 3dbsirofzbenzoylaperoxidewidthcagitation maintaining the. temperature at about 180 to 200 F. The treatment was continued until a sample showed areduced viscosity of about 46 seconds 'Furol at 210 F. Upon dilutiomwith a '75 vis. mineralpale oil to a30*%"sulfonate content, a -viscosity for the "extended solution Of"335 seconds -Baybolt at 100 F; was obtained.

'Wherev-er' the 1 expression oxidation agent or 1 such' similar term =-is -used herein; the. same is :intended to 'designate' any: agentmncombination of agents having orccapable of establishingan oxida- -tiom p'otential =in=ithe petroleum-mahogany sulfonate solution, :to' -be treated there-w'ith, :by rea- -son of what is conventionally :termed available oxygen; and in its broadest aspe'ots includes ac- 'ti-vated oxygen, i. e., ox ygen activated'iby suit- :ableiinductively or oatalyticallyacting agentszas 'is welhknown in the art.

'within 'the broad concept or the-invention it'is of advantage to usesanamount of oxidation agent equivalent :to an avail'able oxygen content -of 0.2"to 15% -Oz by weight of sulfonatedn solution. I

The viscosity-"reducing reactiorr=inaccordance 'with the invention is preferably" carried out in the presence of relatively small amounts-of en electrolyte, i. e., any compound ionizable in the :medium :in which .-the.-.treatment .is carried out to impart electrical conductivity -to. the medium. Most. substantially-water soluble organic ;and :inorganic :acids, bases and salts (are such electroilytes. Many-o the -oxidation.agentsi,usefuLin accordance with the. invention-.asvforexample sbichromates, chromic: acid, ,permanganates, .etc., are, assuch; electrolytes. Others, suchasibenzoyl peroxide and similar compoundsv .are converted to yield electrolytesduring-the oxidation reaction. There are, however, some oxidation agents which are neither, as such;- electrolytes nor are capable .Of .producingtan:electrolyteduring the oxidation :reactiomsuch-as, for-instanca of. hydrogenmeroxide-1or:th e like. ..With these latterw-it maybeinecessary to addsmalliamounts .of ian electrolyte such-as 0.5-3%of NECLxNQdSOmOIHOthGI suitable electrolyte. material (by rweight .oi rsulfonate). :Forthe ,purpose of- .obtaining the best effect .of the electrolyte -whenwcarrying .out v.the viscosity reducing reaction in. accordancewiththe. invention it is' preferredto .proeeed .in-.the .presenceof relatively small amounts of water as for instance conventionally presentdn sulfonate stocks. The -water contentsis=preferablyaat least 05 tor -1 by :weight .ofsulfonates. in solution. Excess amounts =of-.electrolyte or WEtGIYxBIB'HOt critical Ithough they may-entail theinconvenience of salt: or water removal steps respectively.

i Theforegoing'description is ion-purposes :of =illustration-andinot ofrlimitation andiitjsdahere- .fore our intention that the inventionhe limited only by the appended; claims :orvtheir; equivalents wherein We have-endeavored to zrclaim .zbroadly all inherent novelty.

We claim:

.li Process =for reducing the viscosity i of :pet roleum .mahogany sodium sulfonate solutions -which:comprises =reactinge petroleum mahogany sodium 'sulfonatelsolution in an organic substantially waterlimmiscible-sol-vent fortsaid'sulfonate,

said vesolutioni'containing 31;. :least about '23'%130f said sulfonate and'havingza'viscosity of in excess of 600 seconds. Saybolt at 100 F. by .reason -of said sulfonate, with an oxidation agent having an oxidation potential .in said solutionby reason of available"02,: -and selected" from the group consisting of chromic acid, dichromates, permanganates, perchlorates and peroxides, in amount and for a period of time sufficient to reduce the said viscosity of such hydrocarbon solution to a point sufiiciently-low -to yield for asulfonate contentof said solution of' 28 to 40%, a viscosity below-600 seconds Saybolt at 100 F.

2. Process-for reducing viscosity of petroleum mahogany sodium sulfonate solutions which comprises reacting a petroleum mahogany sodium sulfonate solution in retained oil, said solution containing in excess of 28% of said sulfonate and having a viscosity of in excess of 600 seconds Saybolt at 100 F. by reason of said sulionate, in the presence of small amounts of water, and of anelectrblytewithan oxidation agent, having an oxidation potential in said solution by reason of available Oz,-and selected from'the group consisting of chromic acid, dichromates, permanganates, perchlorates, and peroxides, in amount and for a period of time sufiicient to reduce said viscosity to apoint sufl'iciently low to yield for a sulfonate content of said solution of 28 to 40% a'viscosity-below 600 seconds Saybolt at 100 F.

3. Process in accordance with claim Zinwhich .said oxidation agent is an organic peroxide.

"4. Process for reducing the viscosity of petroleum mahogany sodium sulfonate solutions which comprises reacting,in the presence of small amounts of water and of an electrolyte, a solution of in excess of 28% petroleum mahogany sodium sulfonate' in a solvent forsaid sulfonate of the petroleum hydrocarbon type, said hydrocarbon solvent having a viscosity substantially between 40 and 150 seconds Saybolt'at'100F. and said solution having a viscosity of in excess of 600 seconds Saybolt at 100 F.rbyreason of said'sulfonate dissolved therein, with an oxidation agent. having an oxidation potential in said solution by reason of available 02, and selected from the group consisting of chromic acid, dichromates, permanganates, perchlorates and peroxides, and in amount equivalent toan available oxygen content of 0.2'to 1.5% '02 by way of sulfonates in solution, and for a'period of' time sufficient to reduce the normally relatively high viscosity of said solution-due to the 'saidsulfonate dissolved therein 'to a' point sufficiently low to yield 'for asulfonate content from 28 to 40%, a viscosity below 600 seconds Saybolt at 100 F.

5. Process in accordance with claim 4 in'which said oxidation agent is an organic peroxide.

*6. Process forreducing the viscosity of -pet- 'roleum mahogany sodium sulfonate solutions which comprises "reacting, in the presence of small amounts of-water and of an electrolyte, a-solution in excess of 40% 'petroleum mahogany sodium sulfonate'in retained" oil, with an oxidation agent having 'anoxidation potential in said solution by reason of available Oz'in amount equivalent to available oxygen contentof 0.2 to 1.5% Oz by weight of sulfonates in solution, and selected from the group consisting of chromic -acid; dichrom'ates, 1 i permanganates, perchlorates and peroxidesand i for a :period of time i sufiicient 1 to reduce the "relatively "high :viscosity 1 of said solution due to the said --sulfonate "clissolved 'therein-ito a point sufdcieritly lowto yield upon LEO LIBERTHSON. JACOB FAUST.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,367,435 Ruedrich Jan. 16, 1945 5 2,361,476 Higbee Oct. 31, 1944 2,307,743 Liberthson Jan. 12, 1943 OTHER REFERENCES Sodium Chlorite, by Taylor et al. in Industrial 10 and Engineering Chemistry of July 1940, pages 899 and 900 pertinent. 

